No date has yet been set for the change.
The brief spans product and corporate PR, including handling of the mint's annual results, and crisis and internal communications. The winning agency will report to head of corporate affairs Martin Cragg.
Meanwhile, the mint is searching for a CEO following the reported 'sudden' departure of Gerald Sheehan in January. He left the organisation after four years at its helm to 'pursue other interests'.
Details of the brief are on public sector tendering service Infobrokers' website, www.infobrokers.co.uk.